Triple-expansion mallet locomotive



1,629,369 S. M. VAUCLAIN Filed Nov. 2.5, 1925 2 Sheets-Sheet" 1 TRIPLE EXPANSION MALLET LOCOMOTIVE v as V. o 0 Q 0 o Q G e o W 0 Q w MW mm m w u o\ w I W May 179 1927.

May 17, 1927. 1,629,369

S. M. VAUCLAIN TRIPLE EXPANSION MALLET LOCOMOTIVE Filed Nov. 2 1925 Sheets-Sheet 2' Patented May 17, 1927.

UNITED STATES.

1,629,369 PATENT- oFF-IcE.

SAMUEL M. VAUCLAIN, OF ROSEMONT, PENNSYLVANIA. ASSIGNORTO THE BALDWIN LOCOMOTIVE WORKS, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

TRIPLE-EXPANSION MALLET LOCOMOTIVE.

Application filed November 25, 1925. Serial No. 71,406.

Figs. 2", 2" and 2 are enlarged views con stituting a side elevation of the l0c0motive showing the details of constructlon.

Referring to Fig. 1 of the drawlngs, 1 is the boiler, which is rigidly secured to the frame'2 of the locomotive. This frame 2 also carries the intermediate cylinders 3, 2 the saddle 4 of which is secured to the boiler, as shown in Fig. 1, and in detail in I Fig. 2".

The forward end of the boiler overhangs the forward frame 6, which is connected to the frame 2 by an articulated joint 7 of ordinary construction. Bearing-blocks 8 on the boiler are arranged to slide on the supporting pedestal 9 of the frame. high-pressure cylinders 10 are carried lay the frame 11 of the tender 12, and the ten er-frame 11 is connected to the rear end of the frame 2 by an articulated joint 13, so that there are three frames which support the boiler and the tender. On each frame are boxes for the axles 14,

14 and 14", on which are mounted the driving-wheels 15, 15 and 15 The wheels of each frame are connected b rods and to the piston-rods in the ordinary manner; This construction is omitted to avoid confusion.

High-pressure steam is taken from the steam space of the boiler through the pipes 16 and 16" within the boiler and smoke-box, Fig. 2, and through a pipe 16 extending outside of the boiler to the extreme end of the fire-box, and communicates with a pipe 16 which has a universal joint connecting it with the cylinders 10. This joint accommodates itself to the movement of the rear frame on the pivot 13 by which it is connected to the frame2.

The exhaust steam from the high-pressure The cylinders passes through a pipe 17 which is connected by a ball-joint with the pipe lead- 5. ing from the higlnpressure cylinders and extends to, and communicates with, the inlet passages of the valve-chests of the intermediate cylinders 3.

The exhaust from the intermediate cylinders 3 passes through a pipe 18 which. is connected to the exhaust pipes of the cylinders 3 by means of a ball-joint. The pipe 18 extends to and communicates with a pipe 19 which leads to the steam inlet ports of the valve-chests of the low-pressure cylinders 20 carried by the forward frame 6. The exhausts from the cylinders 20 are coupled to the nozzle 21 through a pipe 22, having'a telescopic section which accommodates itself to the movement of the frame ,6 in respect to the boiler (see Fig.

While I have shown in Fig. 1 each frame having four driving-wheels at each side coupled to the iston of the respective cylinders, the num er of driving wheels may be varied, according to the type of locomotive to which my invention is applied. By the above construction, a comparatively'compact triple expansion locomotive of the Mallet type is' produced, in which the several frames are connected byarticulated joints, and the length of the individual frames is no greater than the length of the frames of an ordinary Mallet locomotive.

I claim: I

1. The combination in a triple expansion locomotive of the Mallet type, of a rear frame of the locomotive; a boiler secured to said frame; a forward frame connected by an articulated joint with the frame that supports the boiler, said boiler overhanging the said forward frame; low-pressure cylinders mounted on the forward frame; intermediate cylinders mounted on the frame that supports the boiler; a tender frame pivotally connected to the rear frame of the locomotive; high-pressure cylinders located at the forward end of the tender frame; pipe connections between the boiler and the highpressure cylinders, between the high-pressure cylinders and the intermediate cylinders, and between the intermediate cylinders and the low-pressure cylinders; and an exhaust pipe connecting the low-pressure cylinders with a nozzle in the smoke-box of the boiler.

2. The combination in a 1ocomotive,.of

three frames; a boiler,rigid-ly connected to and supported by the intermediate frame and overhanging the forward frame; a tender mediate cylinders mounted on the intermediate frame; high-pressure cylinders mounted on the rear frame; a steam supply pipe leading from the boiler to the valvechests of the cylinders on the rear frame; pipes connecting the high pressure cylinders with the intermediate cylinders, and the intermediate cylinders with the low-pressure cylinders, said frames being connected by articulated joints; and steam pipes between the high-pressure cylinders and the intermediate cylinders, the intermediate cylinders and the low-pressure cylinders being coupled by ball-joints.

3. The combination in a triple expansion locomotive, of three pivotally connected frames; a boiler rigidly secured to the central frame and overhanging the forward frame; high-pressure cylinders carriedby the rear frame; intermediate cylinders carried by the frame that supports the boiler; low-pressure cylinders carried by the for- ,Ward frame; a steam pipe connecting the boiler with the high-pressure cylinders; exhaust connections for the low-pressure cylinders; and pipes connecting the intermediate cylindcrs with thehighand low pressure cylinders.

SAMUEL M. VAUCLAIN, 

